The ultimate objective of this study is to assess the long-term iatrogenic effects of the various modalities of therapeutic intervention in breast cancer included in the first two collaborative clinical studies. Secondary objectives are further assessment of long-term therapeutic effects and benefit-to-cost assessments. The goals for the current year are to assess the feasibility of various follow-up strategies that might be used in the eventual study and to produce preliminary information which, together with further information generated during the period of the continuation, could provide the basis for a renewal grant proposal that would make it possible to achieve the ultimate objectives of this study. The specific significance of the proposed project is that it has a reasonable prospect of answering important questions about the treatments of breast cancer which are currently of concern to both physicians and patients. Since the study operates from a unique data base which was randomized with respect to treatment arms and this was also randomized with respect to long-term iatrogenic effects, the principal methodological problem in this study is to secure completeness of follow-up.